i mean, after all, abraham, a single man, managed to do so and mohammed, a single individual, managed to do so. the human spirit is remarkable if people simply put their mind to accomplishing what they feel god calls them to do. >> whatever accounts for christianity's success, the debates over what the faith in jesus is and what organized religion should be are far from settled. >> in the beginning of christianity there is diversity. there are different points of view, different interpretations of jesus, different ways of understanding god and the world. and in the beginning, there is no orthodoxy and heresy. >> but that situation did not last for long, and much of the first 300 years of christianity and beyond were spent defining that faith. >> the struggle regarding orthodoxy and heresy never comes to an end, and these battles about truth and inclusion and exclusion are with us to the present day. >> sometimes we say if we could just get back to new testament christianity, then the church would live in unity.